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<h1>Overview</h1>
<p>The Meta data source is so named because it is able to combine existing points into new points. Rather than deriving its information from an external source, it uses the values of other points, allowing them to be manipulated in arbitrary ways.</p>

<h1>JavaScript / ECMAScript</h1>
<p>This data source requires some knowledge of JavaScript, also known as ECMAScript. (The full specification for ECMAScript is available <a href="http://www.ecma-international.org/publications/standards/Ecma-262.htm" target="_blank">here</a>.) JavaScript is arguably the most popular scripting language in use today, it being the only language available for use in every popular web browser. The result is that, by far the common usage of JavaScript is in web pages. The context within the Meta data source is of course different, there being no "window" or "document" objects, among other more subtle differences. Contextual differences aside, a full and complete implementation of ECMAScript is available within this data source. Specifically, the <a href="http://www.mozilla.org/rhino/" target="_blank">Rhino</a> implementation is used.</p>